#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<math.h>
double up(double x)
{
	int x1 = (int)x;
	if (x - x1 > 0.5) x1++;
	return x1;
}
int main()
{
	double d, v;
	scanf("%lf%lf", &d, &v);
	int tmp = 1, t = 0;
	if (v == d)
	{
		printf("1");
		return 0;
	}
	while (v > 0)
	{
		t += tmp + 1;
		v -= tmp * d;
		tmp++;
		if (v - tmp * d < 0) break;
	}
	if (v == 0) t--;
	double r = v / d;
	int r1 = r;
	if (r - r1 > 0) r1++;
	t += r1;
	printf("%d", t);
	return 0;
}